Ecosystem types

South Africa has 290 estuaries and 42 micro-estuaries, which have been classified into 22 estuarine ecosystem types and 3 micro-estuary types. This high diversity of estuary types stems from the country’s diverse climatic, oceanographic and geological drivers.

The Goukamma Estuary, a Warm Temperate Large Temporarily Closed type, is in a Marine Protected Area and in a near-natural condition, yet under pressure from flow reduction, pollution, fishing, riparian development and artificial breaching. (© Cape Nature)

Estuary ecosystem types can serve as surrogates for ecosystem processes and enable predictions of biophysical characteristics. Understanding ecological processes and patterns associated with an estuary type facilitates an assessment of its resilience to anthropogenic pressures. This allows for extrapolation in data-limited environments (see Figure 1).

The estuarine classification scheme divided the biogeographical regions that characterise the South African coast into four major zones: the Cool Temperate (Orange to Ratel), the Warm Temperate (Heuningnes to Mendwana), the Subtropical (Mbashe to St Lucia) and the Tropical (uMgobezeleni to Kosi), with the latter being a new addition to the estuarine biogeographical regions.

All rivers or streams with outlets to the sea were categorised broadly as estuaries and micro-systems. South Africa’s 290 estuaries are categorised into nine functional types, namely Estuarine Lake, Estuarine Bay, Estuarine Lagoon (e.g. the groundwater-fed Langebaan system), Predominantly Open, Large and Small Temporarily Closed, Large and Small Fluvially Dominated, and Arid Predominantly Closed. Micro-systems were further divided into micro-estuaries (42), micro-outlets, and coastal waterfalls based on spatial features and biotic observations in the field.

Figure 1. Estuarine ecosystem typology

Biographical regions

The traditional biogeographic organisation of South African estuaries has included only three dominant regions, viz. subtropical, warm temperate and cool temperate^1–3. However, the tropical distribution of some species recorded in the Kosi and uMgobezeleni estuaries in the north, prompted subdividing the subtropical region and include a tropical transition zone in the north-east of South Africa. Both of these systems, albeit differing in size and function, are unique clear water estuaries on a small section of South African coast.

Kosi Estuary has uniquely tropical flora indicated by presence of the seagrass (Halodule universis) and mangrove species Lumnitzera racemosa, Ceriops tagal and Xylocarpus granatum that are found in no other South African systems⁴. Tropical species such as the snake sea cucumber (Synapta maculate) and pen shell (Pinna muricata) (associated with H. universis) also point to a tropical influence on the system’s invertebrate fauna. The ichthyofaunal comprises a wide diversity of fishes, including tropical species not reported from any other South African estuaries⁵. This is evidenced by the abundance and large sizes of several members of the Lutjanidae (snappers) in the system.

St Lucia Estuary, to the south of Kosi, supports invertebrate communities common in subtropical estuaries⁶. The tropical zone, therefore, aligns with marine biogeographic patterns evident in the marine biogeographic map (the Natal-Delagoa tropical region)⁷.

Thus, the Estuarine Ecosystem Classification scheme defined the biogeographical regions as:

• Cool temperate from Orange Estuary on the Northern Cape to Uilkraals Estuary in the Western Cape;

• Warm temperate from the Ratel Estuary near Cape Agulhas to Mendwana Estuary in the Eastern Cape;

• Subtropical stretches from the Mbashe Estuary in the Eastern Cape to the St Lucia Estuary in KwaZulu-Natal; and

• Tropical from uMgobezeleni to Kosi Estuary in Northen KwaZulu-Natal.

What is an estuary?

The NBA 2025 defines an estuary as ‘a partially enclosed permanent water body, either continuously or periodically open to the sea on decadal time scales, extending as far as the upper limit of tidal action, salinity penetration or back-flooding under closed mouth conditions. During floods an estuary can become a river mouth with no seawater entering the formerly estuarine area or, when there is little or no fluvial input, an estuary can be isolated from the sea by a sandbar and become fresh or even hypersaline’⁴. A defining feature of this definition is that complex estuarine abiotic processes distinguish estuaries from other aquatic ecosystem types, i.e. restricted tidal action, mixing of fresh and salt water, increased retention and/or increased water levels under closed mouth conditions.

Estuary functional types

South Africa’s 290 estuaries are categorised into nine functional types, namely Estuarine Lake, Estuarine Bay, Estuarine Lagoons (e.g. the groundwater-fed Langebaan system), Predominantly Open, Large and Small Temporarily Closed, Large and Small Fluvially Dominated, and Arid Predominantly Closed (see Figure 2).

Figure 2. Examples of South African estuary types.

Estuarine Lakes

Estuarine Lakes comprise one or more typically large circular water bodies connected to the sea by a constricted inlet channel. Maximum water levels are determined by berm height, mouth state and freshwater input. Marine connectivity varies from almost permanently open to closed on annual scales. Salinities are highly variable, ranging from fresh to hypersaline because of differing freshwater input (surface and ground water), evaporation and the extent of the marine connection. Mixing processes are dominated by wind and, to a lesser extent fluvial inputs, owing to their restricted mouths and relatively large surface areas. Sediment processes tend to be stable, with infilling occurring over long time scales and resetting confined to larger flood events.

Estuarine Bays

Estuarine Bays are permanently linked to the sea by unrestricted, deep mouths and are dominated by tidal processes, with tidal amplitudes close to those of the sea. These are large systems (>1 200 ha) with generally round basins where only the upper reaches experience a degree of constriction to tidal flows. As a result of relatively low river inputs they have a predominantly euhaline salinity regime in the lower and mid reaches, with freshwater mixing processes being mostly confined to the restricted upper areas. Sediments are typically marine in origin and grain size distributions are stable. There are two natural occurrences of Estuarine Bays in South Africa (viz. Knysna and Durban Bay).

Estuarine Lagoons

Langebaan Lagoon has many of the characteristics of an estuary⁸, including calm waters that are protected from marine wave action and biota that reflect many of the species usually found in estuaries. However, despite groundwater seeps into some areas, it lacks surface water inflow and a normal estuarine salinity gradient. Langebaan Lagoon represents a unique coastal ecosystem type and is recognised as an estuary because its ecological functioning includes both freshwater and marine inputs into a semi-enclosed embayment. Estuarine Lagoons, as defined here, are permanently connected to the sea and are therefore marine dominated. Tidal action is the dominant mixing process and sedimentary processes are thus generally stable. Tidal amplitude and water levels are close to those of the sea.

Predominantly Open estuaries

These estuaries are open to the sea for more than 90% of the time. Some are permanently open owing to perennial river flows or the presence of large tidal prisms. Predominantly Open estuaries are linear systems in which mixing processes are dominated by both fluvial inputs and tidal action creating vertical and horizontal salinity gradients. Under low flows, hypersalinity can develop in the upper reaches. The degree to which the mouth is restricted depends on the rate and volume of freshwater inflow. Some systems become severely constricted during low flow periods. Regular flooding results in relatively mobile sediments. These estuaries usually support wetlands, salt marshes, macrophyte beds and marine and estuarine fauna. Surprisingly, their size varies considerably ranging from 10 to 7500 ha, with smaller systems afforded a degree of protection against direct wave action by rocky headlands or subtidal reefs, which assists in maintaining an open mouth.

Large and Small Temporarily Closed estuaries

The sizeable temporarily open/closed category of Whitfield (1992)⁹ was divided into Small and Large Temporarily Closed estuaries using a total habitat area of 15ha (associated with ~10 ha of open water area) as the dividing threshold. The division was based on differences in biophysical processes and patterns. Small systems are likely to experience rapid increases and decreases in freshwater runoff over a few hours making them strongly event driven. There will be little scouring during breachings, and a semi-closed mouth condition can easily develop owing to a small, perched, outflow channel that restricts tidal amplitude to 10 to 15 cm. There is minimal water column area during the open state. Habitat diversity is likely to be low (and without intertidal salt marshes) and species diversity and abundance reduced.

Both large and small systems tend to be linear or funnel shaped with highly restricted inlets. Smaller systems especially tend to be ‘perched’ above normal tidal levels, resulting in little to no open water area during the open mouth low tide state. Water levels are dominated by the state of the mouth, with highest levels of 1 m to 2 m above mean sea level during the closed phase. Open phase mixing processes are dominated by fluvial input and partially by tides. When closed, wind and seepage losses through the berm play a key role. Sediment composition is largely stable, resetting mainly during floods. Salinity regimes range from almost fresh to hypersaline, as that latter can develop during times of low flow or droughts in large systems. Small Temporarily Closed estuaries tend to be fresher in character as they have less connectivity with the sea.

Small and Large Fluvially Dominated estuaries

The classification distinguishes between small (<15 ha), black water dominated, rocky temperate southern coast estuaries; and large (≥15 ha), shallow, sediment rich, freshwater dominated systems of the east and west coasts. The larger systems have very high sediment turnover, often develop ebb-tidal deltas, are turbid and can close during periods of low flow, e.g. uThukela and Orange estuaries. Small, sediment-starved, fluvially-dominated systems have unrestricted mouths as they usually occur along rocky shores and receive clear humic-stained water from Table Mountain Sandstone catchments. Large Fluvially Dominated estuaries tend to be constricted and can even periodically close during low flows. River processes are dominant and salinities are mostly fresh throughout the estuary for more than half the time. During peak flood conditions, outflows can influence salinities for considerable distances offshore.

Arid Predominantly Closed estuaries

This type comprises six small estuaries (Buffels, Swartlintjies, Spoeg, Groen, Sout (Noord) and Wadrift) located in the arid Namaqua West Coast region. They are linear or funnel shaped and closed on annual to decadal scales. Salinities tend to be high to hypersaline (>35) as a result of low fluvial input and high evaporation rates. Thus, mixing processes tend to occur over long time periods and are dominated by the effects of evaporation, winds and seepage. Occasional breaching and over-washing during high sea conditions provide for marine connectivity. Sediment processes are generally stable on decadal time scales and are reset by large intermittent flash floods. Water levels are determined by the interplay between sand berm level, evaporation rates and seepage losses. Groundwater and inflows from local fountains replenish these losses and influence the salinity regimes of these estuaries.

Arid conditions promote the growth of unique vegetation such as salt tolerant, succulent Sarcocornia spp. and Salicornia spp. that can flourish despite open water salinities reaching above 200. Fish species rely on ‘suicidal’ recruitment that is largely a function of connectivity with the sea and overwash during high seas. Fish survival depends on groundwater maintaining salinity gradients and hypersalinity not exceeding 40 in parts of the systems. Invertebrate diversity, abundance and community structure are related to changing salinity gradients including long cycles of hypersalinity, e.g. Shrimp Artemia sp. that hatch at salinities above 40 and encyst when salinities exceed 150. Cycles of Artemia abundance follow salinity regimes that in turn affect the diversity, abundance and occurrence of flamingos and other birds that feed on them.

Estuarine ecosystem types in South Africa

The Estuarine Ecosystem Classification system for South Africa’s 290 estuaries are derived from interplay between biogeographical regions and estuary functional types, stemming from the country’s diverse climatic, oceanographic and geological drivers.

Estuarine Lagoons are the rarest South African estuary type with only one member in the Cool Temperate region, followed by Estuarine Bays with two in the Subtropical and one in the Warm Temperate region. Arid Predominantly Closed estuaries are confined to six systems in the Cool Temperate region. The Large and Small Fluvially Dominated types comprise seven systems each, occurring in three and two biogeographical regions, respectively. Small Temporarily Closed (116), Large Temporarily Closed (93), and Predominantly Open (45) are the most dominant types occurring across the Cool Temperate, Warm Temperate and Subtropical biogeographical regions. Estuarine Lakes occur across all four biogeographical zones. While not numerically dominant, this type represents the largest surface area of all estuary functional types, with Lake St Lucia representing more than half of South Africa’s estuarine surface area.

Estuary name	Estuary type	Estuary functional type	Protection level	Threat status	Condition	Extent (ha)
Orange	Cool Temperate Large Fluvially Dominated	Cool Temperate	Poorly Protected	Endangered	Heavily modified	3019.1
Buffels	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	87.6
Swartlintjies	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Near-natural	134.3
Spoeg	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Near-natural	88.2
Groen	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Near-natural	88.2
Sout (Noord)	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	532.8
Olifants	Cool Temperate Predominantly Open	Cool Temperate	Not Protected	Endangered	Moderately modified	2778.6
Jakkals	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	72.6
Wadrift	Cool Temperate Arid Predominantly Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	509.0
Verlorenvlei	Cool Temperate Estuarine Lake	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	2276.3
Groot Berg	Cool Temperate Predominantly Open	Cool Temperate	Not Protected	Endangered	Heavily modified	11733.5
Langebaan	Cool Temperate Estuarine Lagoon	Cool Temperate	Moderately Protected	Endangered	Near-natural	6006.9
Diep/Rietvlei	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	1250.0
Sout (Wes)	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	613.7
Disa	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	23.5
Wildevoëlvlei	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	604.8
Schuster	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Near-natural	22.6
Krom	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Natural	100.5
Silwermyn	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	15.8
Zand	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Heavily modified	381.8
Zeekoei	Cool Temperate Estuarine Lake	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	405.5
Eerste	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Severely / critically modified	277.4
Lourens	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Heavily modified	266.5
Sir Lowry’s Pass	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Severely / critically modified	4.1
Steenbras	Cool Temperate Small Fluvially Dominated	Cool Temperate	Well Protected	Vulnerable	Near-natural	4.0
Rooiels	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Natural	21.6
Buffels (Oos)	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Near-natural	35.8
Palmiet	Cool Temperate Large Temporarily Closed	Cool Temperate	Poorly Protected	Endangered	Moderately modified	44.2
Bot/Kleinmond	Cool Temperate Estuarine Lake	Cool Temperate	Poorly Protected	Endangered	Moderately modified	2345.9
Onrus	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Heavily modified	30.8
Klein	Cool Temperate Estuarine Lake	Cool Temperate	Poorly Protected	Endangered	Moderately modified	2065.5
Uilkraals	Cool Temperate Predominantly Open	Cool Temperate	Not Protected	Endangered	Heavily modified	747.7
Ratel	Cool Temperate Small Temporarily Closed	Cool Temperate	Moderately Protected	Vulnerable	Near-natural	35.9
Heuningnes	Warm Temperate Estuarine Lake	Warm Temperate	Moderately Protected	Endangered	Heavily modified	10993.7
Klipdrifsfontein	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	6.7
Breede	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	2257.6
Duiwenhoks	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	441.4
Goukou	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	438.7
Gouritz	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	1099.7
Blinde	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	19.9
Tweekuilen	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Severely / critically modified	23.2
Gericke	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Severely / critically modified	8.7
Hartenbos	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	306.1
Klein Brak	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	1021.7
Groot Brak	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	318.1
Maalgate	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	34.4
Gwaing	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	21.8
Kaaimans	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	40.6
Touw/Wilderness	Warm Temperate Estuarine Lake	Warm Temperate	Moderately Protected	Endangered	Moderately modified	1180.4
Swartvlei	Warm Temperate Estuarine Lake	Warm Temperate	Moderately Protected	Endangered	Near-natural	2168.2
Goukamma	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	299.2
Knysna	Warm Temperate Estuarine Bay	Warm Temperate	Moderately Protected	Vulnerable	Near-natural	3010.6
Noetsie	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	50.6
Piesang	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	87.3
Keurbooms	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	1623.8
Matjies	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	12.1
Sout (Oos)	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Natural	24.1
Groot (Wes)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	100.0
Bloukrans	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Natural	15.3
Lottering	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Natural	11.2
Elandsbos	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Natural	22.1
Storms	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Natural	12.4
Elands	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Near-natural	31.1
Groot (Oos)	Warm Temperate Small Fluvially Dominated	Warm Temperate	Well Protected	Least Concern	Natural	30.3
Tsitsikamma	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	67.4
Klipdrif (Oos)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	66.8
Slang	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	42.8
Kromme	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	755.5
Seekoei	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	322.4
Kabeljous	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	311.9
Gamtoos	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	2133.4
Van Stadens	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	101.8
Maitland	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	67.6
Baakens	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Severely / critically modified	13.5
Papkuils	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Severely / critically modified	80.4
Swartkops	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	2861.0
Coega (Ngqurha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Severely / critically modified	443.5
Sundays	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	824.0
Boknes	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	47.5
Bushmans	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	888.8
Kariega	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	559.0
Grant's	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	16.3
Kasouga	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	247.6
Kowie	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	484.9
Rufane	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	24.7
Riet	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	40.3
West Kleinemonde	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	224.2
East Kleinemonde	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	100.9
Great Fish	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	519.9
Old Woman’s	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	23.3
Mpekweni	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	83.1
Mtati (Mthathi)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	142.1
Mgwalana	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	216.9
Bira (Bhirha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	270.6
Gqutywa	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	105.4
Ngculura (Ngculurha)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	36.6
Mtana	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	81.2
Keiskamma	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	1402.0
Nqinisa	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	54.3
Kiwane (Khiwane)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Natural	87.0
Tyolomnqa	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	207.6
Shelbertsstroom	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	15.0
Lilyvale	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	33.7
Ross' Creek	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	13.0
Ncera (Ncerha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	77.9
Mlele	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	20.2
Mcantsi	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	31.8
Gxulu	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	106.6
Goda	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	51.9
Hlozi	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	40.9
Hickman's	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Moderately modified	25.9
Buffalo	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Heavily modified	137.5
Blind	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Heavily modified	14.3
Hlaze (iHlanze)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Heavily modified	7.9
Nahoon	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Moderately modified	178.5
Qinira (Quinirha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	110.7
Gqunube	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	176.3
Kwelera (Kwelerha)	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	121.6
Bulura (Bulurha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	135.4
Cunge	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	8.7
Cintsa	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	122.6
Cefane	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	176.5
Kwenxura (Kwenxurha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Natural	126.1
Nyara (Nyarha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	55.3
Imtwendwe (Mtwendwe)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	15.9
Haga-haga	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	25.5
Mtendwe	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	17.1
Quko	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Natural	102.1
Morgan	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	83.5
Cwili	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	14.7
Great Kei	Warm Temperate Large Fluvially Dominated	Warm Temperate	Not Protected	Vulnerable	Moderately modified	572.6
Gxara (Gxarha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	68.5
Ngogwane	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	22.5
Qolora (Qolorha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	69.3
Ncizele	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	22.9
Timba	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	9.2
Kobonqaba (Khobonqaba)	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	115.1
Nxaxo/Ngqusi	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	269.5
Cebe	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Natural	82.1
Gqunqe	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Natural	79.1
Zalu	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	68.8
Ngqwara (Ngqwarha)	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	78.9
Sihlontlweni	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	55.2
Nebelele	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	29.8
Qora (Qhorha)	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	133.9
Jujura (Jujurha)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	30.3
Ngadla	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	40.7
Shixini	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Natural	116.4
Beechamwood	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	20.1
Kwazlelitsha (Kwazwedala)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	32.1
Kwa-Goqo	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	30.9
Ku-Nocekedwa	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	33.7
Nqabara/Nqabarana	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	307.8
Ngomane (East)	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Near-natural	25.9
Ngoma/Kobule	Warm Temperate Small Temporarily Closed	Warm Temperate	Moderately Protected	Least Concern	Natural	88.8
Mendu	Warm Temperate Large Temporarily Closed	Warm Temperate	Poorly Protected	Vulnerable	Near-natural	107.4
Mendwana	Warm Temperate Predominantly Open	Warm Temperate	Poorly Protected	Vulnerable	Natural	27.8
Mbashe	Subtropical Large Fluvially Dominated	Subtropical	Poorly Protected	Endangered	Moderately modified	469.8
Ku-Mpenzu	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	31.7
Ku-Bhula (Mbhanyana)	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	58.7
Kwa-Suku	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	21.4
Ntlonyane	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	89.7
Nkanya	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	62.1
Sundwana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	25.2
Xora	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	261.5
Bulungula	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	67.4
Ku-Amanzimuzama	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	13.0
Nqakanqa	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	16.9
Mdikana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	17.0
Mncwasa	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	116.7
Mpako	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	51.5
Nenga	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	33.6
Mapuzi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	12.2
Mtata	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Moderately modified	545.6
Thsani	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	12.6
Mdumbi	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	254.9
Lwandilana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	49.6
Lwandile	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	100.5
Mtakatye	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	247.8
Hluleka	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	30.1
Mnenu	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	197.0
Mtonga	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	56.2
Mpande	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	51.3
Sinangwana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	123.1
Mngazana	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	770.6
Mngazi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	434.3
Gxwaleni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	16.1
Bulolo	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	13.2
Mtumbane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	15.5
Mzimvubu	Subtropical Large Fluvially Dominated	Subtropical	Poorly Protected	Endangered	Near-natural	842.7
Ntlupeni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	30.8
Nkodusweni	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	100.0
Mntafufu	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	277.5
Ingo	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	34.7
Mzintlava	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	108.9
Mzimpunzi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	67.8
Kwanyambalala	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	24.8
Mbotyi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	64.1
Mkozi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	38.1
Sikatsha	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	13.3
Lupatana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	14.5
Mkweni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	15.4
Msikaba	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	142.0
Mgwegwe	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	19.4
Mgwetyana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	22.1
Mtentu	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	92.8
Sikombe	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	102.1
Kwanyana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	57.8
Mtolane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Natural	46.5
Mnyameni	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	87.5
Mpahlanyana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	24.1
Mpahlane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	35.2
Mzamba	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Near-natural	110.7
Mtentwana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	33.4
uMthavuna	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	160.0
iSolwane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	18.7
iSandlu	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	32.4
uMbhoyibhoyi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	20.2
uMuntongazi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	11.5
iKhandalendlovu	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	31.6
iMpenjani	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	100.8
uMhlangomkhulu (South) (Umhlangankulu)	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	45.5
iKhaba	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	26.2
iMbizana	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	95.9
iMvutshini	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	10.7
iBilanhlonhlo	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Heavily modified	23.6
uVuzana	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	9.8
iKongeni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Severely / critically modified	44.8
uVunguza	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	14.5
oHlangeni	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	70.3
iZotsha	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	104.0
iBhobhoyi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	47.9
uMbango	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Severely / critically modified	36.7
uMzimkhulu	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Moderately modified	402.9
uMthente	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	102.5
uMhlangomkhulu (North) (Mhlangamkulu)	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	27.9
iDombe	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Heavily modified	27.1
iKhoshwana	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	23.1
iNjambili	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	67.4
uMzumbe	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	291.2
uMhlabashana	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Near-natural	32.5
uMhlungwa	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	43.8
uMfazezala	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	20.9
uMakhosi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	19.0
uMnamfu	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	18.1
uMthwalume	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	185.6
uMvuzi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	36.7
iFafa	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Heavily modified	111.2
uMdesingane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Heavily modified	25.0
iSezela	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	72.7
uMkhumbane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	24.8
iNkomba	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	1.1
uMuziwezinto	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	105.3
uMzimayi	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	26.6
Rocky Bay	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Heavily modified	5.9
uMphambanyoni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	84.4
aMahlongwa	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Moderately modified	98.1
uMahlongwane	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	40.7
uMkhomazi	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Moderately modified	331.9
iNgane	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Heavily modified	34.6
uMgababa	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	138.0
uMsimbazi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	193.7
iLovu	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Heavily modified	425.4
aManzanamtoti	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Severely / critically modified	55.2
aManzimtoti	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	50.3
iZimbokodo	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	89.4
iSiphingo	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	704.4
Durban Bay	Subtropical Estuarine Bay	Subtropical	Not Protected	Critically Endangered	Severely / critically modified	2815.2
uMngeni	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	403.5
uMhlanga	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	150.8
uMdloti	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Heavily modified	189.5
uThongathi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Severely / critically modified	145.6
uMhlali	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Heavily modified	200.9
Bob’s Stream	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Heavily modified	8.9
uSetheni	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Near-natural	10.2
uMvoti	Subtropical Large Fluvially Dominated	Subtropical	Poorly Protected	Endangered	Heavily modified	288.7
uMdlotane	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	79.9
iNonoti	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	153.8
iZinkwazi	Subtropical Large Temporarily Closed	Subtropical	Poorly Protected	Vulnerable	Moderately modified	300.1
uThukela	Subtropical Large Fluvially Dominated	Subtropical	Poorly Protected	Endangered	Heavily modified	1261.0
aMatigulu/iNyoni	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Moderately modified	1183.1
iSiyaya	Subtropical Small Temporarily Closed	Subtropical	Moderately Protected	Vulnerable	Severely / critically modified	88.4
uMlalazi	Subtropical Predominantly Open	Subtropical	Poorly Protected	Vulnerable	Moderately modified	1851.7
uMhlathuze	Subtropical Estuarine Lake	Subtropical	Moderately Protected	Endangered	Heavily modified	5642.3
Richards Bay	Subtropical Estuarine Lake	Subtropical	Moderately Protected	Endangered	Severely / critically modified	6365.1
iNhlabane	Subtropical Estuarine Lake	Subtropical	Moderately Protected	Endangered	Severely / critically modified	1875.7
iMfolozi/uMsunduze	Subtropical Large Fluvially Dominated	Subtropical	Poorly Protected	Endangered	Heavily modified	7903.7
St Lucia	Subtropical Estuarine Lake	Subtropical	Moderately Protected	Endangered	Heavily modified	67992.2
uMgobezeleni	Tropical Estuarine Lake	Tropical	Moderately Protected	Vulnerable	Near-natural	829.3
Kosi	Tropical Estuarine Lake	Tropical	Moderately Protected	Vulnerable	Near-natural	7337.0

Download the data here.

Technical documentation

Data availability

• Estuarine Ecosystem Map: BGIS

Key publications

Van Niekerk, L, Adams JB, James, N, Lamberth S, Mackay F, Rajkaran A, Turpie J, Weerts S, Whitfield AK. 2020. An Estuary Ecosystem Classification that encompasses biogeography and a high diversity of types in support of protection and management. African Journal of Aquatic Science, 45: 199-216. doi: https://doi.org/10.2989/16085914.2019.1685934

Recommended citation

Van Niekerk, L., Adams, J.B., James, N.C., Lamberth, S.J., Mackay, F.C., Turpie, J.K., Rajkaran, A., Weerts, S.P., & Whitfield, A.K. 2025. Ecosystem types: Estuarine realm. National Biodiversity Assessment 2025. South African National Biodiversity Institute. http://nba.sanbi.org.za/.

References

1. Emanuel, B. et al. 1992. A zoogeographic and functional approach to the selection of marine reserves on the west coast of south africa. South African Journal of Marine Science 12: 341354.

2. Harrison, T.D. 2002. Preliminary assessment of the biogeography of fishes in south african estuaries. Marine and Freshwater Research 53: 479–490.

3. Turpie, J.K. et al. 2000. Biogeography and the selection of priority areas for conservation of south african coastal fishes. Biological Conservation 92: 59–72. https://doi.org/10.1016/S0006-3207(99)00063-4

4. Van Niekerk, L. et al. 2020. An estuary ecosystem classification that encompasses biogeography and a high diversity of types in support of protection and management. African Journal of Aquatic Science 45: 199216.

5. Blaber, S. & C. DP. 1981. A revised checklist and further notes on the fishes of the kasi system.

6. MacKay, F. et al. 2010. Macrobenthic invertebrate responses to prolonged drought in south africa’s largest estuarine lake complex. Estuarine, Coastal and Shelf Science 86: 553567.

7. Sink, K.J. et al. 2019. National biodiversity assessment 2018: Technical report volume 4: Marine realm. South African National Biodiversity Institute, Pretoria.

8. Whitfield, A. 2005. Langebaana new type of estuary? African Journal of Aquatic Science 30: 207209.

9. Whitfield, A. 1992. A characterization of southern african estuarine systems. Southern African Journal of Aquatic Science 18: 89103.